One of America’s most prominent Catholic cardinals has resigned after an allegation was made that he sexually abused a teenage boy almost 50 years ago.

Theodore McCarrick, the former archbishop of Washington, wrote to the Vatican offering his resignation on Friday, which was accepted by Pope Francis.

A statement from the Vatican issued on Saturday read: "Yesterday evening the Holy Father received the letter in which Cardinal Theodore McCarrick, Archbishop Emeritus of Washington (USA), presented his resignation as a member of the College of Cardinals.

"Pope Francis accepted his resignation from the cardinalate and has ordered his suspension from the exercise of any public ministry, together with the obligation to remain in a house yet to be indicated to him, for a life of prayer and penance until the accusations made against him are examined in a regular canonical trial."

Mr McCarrick, 88, was ordained in 1958 and rose through the ranks in the Archdiocese of New York before being installed as archbishop of Washington in 2001, a post he held until 2006.

Pope Francis recently criticised the “culture of abuse and cover-up” in the Catholic Church CREDIT: VINCENZO PINTO/AFP/GETTY IMAGES

He is officially retired but continues to travel abroad regularly, speaking on issues such as human rights.

The allegation related to Mr McCarrick’s time in New York. He was accused of sexually assaulting a 16-year-old who was being measured for a new cassock, according to The New York Times.

The claim was investigated for the New York archdiocese by a group of jurists, law enforcement experts, parents, psychologists, and religious figures.

The group judged that the allegations were “credible and substantiated”. Mr McCarrick was removed from public ministry on June 20.

Mr McCarrick said in a statement at the time that he was “shocked” by the report and maintained his innocence. He also said he had co-operated with the investigation.

“My sadness was deepened when I was informed that the allegations had been determined credible and substantiated,” he said in the statement.

Mr McCarrick added: “While I have absolutely no recollection of this reported abuse, and believe in my innocence, I am sorry for the pain the person who brought the charges has gone through, as well as for the scandal such charges cause our people.”

At the time senior US church officials said they had received three allegations of McCarrick's sexual misconduct with adults decades ago, two of which resulted in settlements.

A Catholic University canon law expert, Kurt Martens, noted that this was the first time an order of penance and prayer had been issued before a church trial could take place.

Earlier this year Pope Francis publicly criticsed the “culture of abuse and cover-up” in the Catholic Church, saying it must “never again” be allowed to happen.